Give your simulator superpowers

RocketSim: An Essential Developer Tool
as recommended by Apple

Issue 42
Jul 03, 2025

The time between Christmas and New Years Eve most of us are free. For me, this means time to spend on relaxing, hobbies, and family.

I've been working hard on improving code coverage for unit tests in RocketSim. GitHub announced the Video upload public beta which means that RocketSim is now even more usable for sharing videos on your repositories. I'm aiming to release a bigger update in January featuring a few often-requested fixes.

Besides working on RocketSim I've also been working on a new library called SwiftUIKitView. This week's blog post will tell you all about it.

I hope you will all have a great New Years' Eve. I wish you all the best for 2021 and see you next year!

Oh, and, I'm back on Twitter!

THIS WEEK'S BLOG POST

It's tempting to use SwiftUI today but most of us still have a project written in UIKit. With this week's blog post I'm hoping to make it a little easier to start adopting SwiftUI in existing projects.

Why you should read this: SwiftUIKitView is a library I created for this

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TWEET OF THE WEEK

This week’s tweet was super easy to pick: 3 new talks released by Apple! It covers several techniques for optimising UI performance, worth checking out!

CURATED FROM THE COMMUNITY

CODE

A few great new resources from Apple arrived this week. Building Layouts with Stack Views, Creating Performant Scrollable Stacks, and Aligning Views Across Stacks. All articles come with great visuals so worth checking out.

I found this blog post by Shaun interesting for two reasons: It’s not only explaining how you can turn SwiftUI views into images but it’s also shows his progress towards finding out how to do it. A great read.

Sarun W. wrote this article a few weeks ago but I only found it this week. It explains how you can manually symbolicate crash reports, something you might not often need but if you do, it’s very useful to know how it works. While you’re at his blog post, make sure to check out his new side menu with a nice overview of the post.

A short but to the point blog post by Sofia Swidarowicz explaining the benefits of using KeyValuePairs in Swift.

Jesse Squires explains a scenario that you might have been running into as well. The order of execution on initialising instances might have an effect on your instance setup. Jesse explains why.

Although I doubt whether you’ll need this often I found it really interesting to read this post by Bruno Rocha explaining how @inlinable and @usableFromInline work and when you need it.

I often reference posts explaining code techniques but it’s not often that I find an article explaining decisions and elements used. Daniel Saidi explains the story behind building the Swedish video streaming app Cineasterna.

NEWS

As Ben Cohen accounted on Twitter, the async/await proposal got accepted. In his tweet, he shows us a dependency graph to create a little overview. I can’t wait for this to arrive and throw away those closures!

VIDEO

A little present from the team behind Objc.Io: SwiftUI Layout Explained video series is free to watch until the end of the year! Don’t miss this opportunity!

THANK YOU

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